I think I read somewhere in the Baltimore Catachism not to take stock in dreams. I looked it up… this is what it said:
Lesson 30: ON THE FIRST COMMANDMENT
319 Q. Do those who make use of spells and charms, or who believe in dreams, in mediums, spiritists, fortune tellers, and the like, sin against the First Commandment?
A. Those who make use of spells and charms, or who believe in dreams, in mediums, spiritists, fortune tellers, and the like, sin against the First Commandment, because they attribute to creatures perfections which belong to God alone.
“Dreams” are caused by the mind being at work while the body is sleeping or at rest. The mind never sleeps; it is always awake and working. Thus when we are asleep the imagination, without the reason to guide it, mixes together a number of things we have seen, heard, or thought of, and gives us strange scenes and pictures. Sometimes what we dream of seems to happen; but that is only because we dream so much that it would be strange if none of the things ever happened. We will generally dream about whatever was on our mind shortly before. We read in the Holy Scriptures that God at times made known His will to certain persons by dreams; as when the king of Egypt dreamt of the great famine that was to come; or when the angel appeared in sleep to St. Joseph, telling him to take Our Lord into Egypt, where Herod the king could not kill him. (Matt. 2).
The dreams mentioned in the Holy Scripture were more frequently visions than dreams. In a vision the things we see are really present, whereas in dreams they are not, but we imagine they are. God no longer makes use of dreams as a means of communicating with His creatures, because His Church will make known to us His will. He sometimes, however, makes known certain things to His holy servants on earth in a very special and private manner: as, for example, when Our Lord appeared to Saint Margaret Mary and told her He would like to have the devotion to the Sacred Heart established. We must always believe what the Church tells us God has made known to it; but when holy people tell us that God revealed special things to them, we are not obliged to believe what they say, unless the Church confirms it. I say we are not obliged–that is, we may if we please; but we would not be heretics and commit sin if we did not believe all the revelations and wonderful things we find recorded in the lives of saints, though they may all be true.
Hope that helps answer your question.